Repeating some bits from the correct answer above BUT I did not create a new developer account. I initially thought I needed to fork out for a new membership. I created a new Apple ID. Then in the project in XCode, Signing & Capabilities, under Team, I 'Add an account' with that new apple ID. Remember to also generate a certificate and have a unique bundle identifier. Hopefully this is straightforward. Then from there, clicked build, it asked me to enter my password a few other times and I clicked 'always allow'. The app magically showed up on my phone with the same 'not trusted device etc etc' and then in Settings > General > VPN & Device Management, the newly created Apple ID appeared with the app I was working on and click Trust. Like many of you, I was like ????, this is hopefully a temporary issue. I have also created a ticket to report this as a bug. Some additional stuff that you might be interested in : I deleted the app on my phone that still thought I was my OG apple ID (gone but not forgotten) Building using react native, metro doesnt seem to be work like it did but the app does so hey

Hello, this is not a permanent solution. I've done this 3 weeks ago and have had to do the same today because the same issue cropped up again. This was my answer in another thread I cant find : Create a new Apple ID (not a developer account because it will ask you to pay). Then in the project in XCode, Signing & Capabilities, under Team, I 'Add an account' with that new apple ID. Remember to also generate a certificate and have a unique bundle identifier. Hopefully this is straightforward. Then from there, clicked build, it asked me to enter my password a few other times and I clicked 'always allow'. The app magically showed up on my phone with the same 'not trusted device etc etc' and then in Settings > General > VPN & Device Management, the newly created Apple ID appeared with the app I was working on and click Trust.